CERN CLOUD experiment finds secret sauce for cloud formation

I don't expect an outbreak of global reason before it is too late. At which time humanity might be glad someone had at least investigated the feasibility of geoengineered salvation. (Which as with all meaningful salvation, to be effective must be withheld until after humanity actually repents of our sins.)

I don't expect it, I demand it, and I'm prepared to enforce my demands with decisive action at whatever level is required in order to insure that they are met.

When considering the potential costs of higher levels of CO2, it is also relevant to consider the potential benefits. NASA satellite photography has shown a remarkable greening of the Earth over the past 30 years.

Water requirements for plants - including food crops - especially in arid and semiarid areas are strongly affected by CO2. Dry climate plants - including many food crops - have a waxy cuticle covering their leaves to reduce water loss. For these plants, most water loss occurs through the stroma, variable size pores in the leaf surface that allow CO2 to enter the photosynthetic apparatus, but which also allow water vapor to leave. Many real ecologists (I don't mean newspaper journalists) have said that the biggest upcoming ecological challenge is likely to be the availability of adequate water of suitable quality for crop irrigation. The largest aquifer in the US Midwest is being unsustainably mined (water pumping exceeding recharge) for irrigation water. This is true for many other places, including much of China and India.

Rain forests will not benefit much from higher CO2 since the limiting factor for plant growth there is solar energy, almost all of which is captured by plants, very little reaching the forest floor. Irrigated corn, wheat, etc., are a different story - available water is the key. Higher CO2 levels mean smaller stroma (smaller directly in proportion to the CO2 concentration) and hence less water needed for irrigation.

What are the relative costs and benefits of higher CO2? Almost all attention has focused on the former at the expense of adequate study of the latter.

When considering the potential costs of higher levels of CO2, it is also relevant to consider the potential benefits. NASA satellite photography has shown a remarkable greening of the Earth over the past 30 years.

Water requirements for plants - including food crops - especially in arid and semiarid areas are strongly affected by CO2. Dry climate plants - including many food crops - have a waxy cuticle covering their leaves to reduce water loss. For these plants, most water loss occurs through the stroma, variable size pores in the leaf surface that allow CO2 to enter the photosynthetic apparatus, but which also allow water vapor to leave. Many real ecologists (I don't mean newspaper journalists) have said that the biggest upcoming ecological challenge is likely to be the availability of adequate water of suitable quality for crop irrigation. The largest aquifer in the US Midwest is being unsustainably mined (water pumping exceeding recharge) for irrigation water. This is true for many other places, including much of China and India.

Rain forests will not benefit much from higher CO2 since the limiting factor for plant growth there is solar energy, almost all of which is captured by plants, very little reaching the forest floor. Irrigated corn, wheat, etc., are a different story - available water is the key. Higher CO2 levels mean smaller stroma (smaller directly in proportion to the CO2 concentration) and hence less water needed for irrigation.

What are the relative costs and benefits of higher CO2? Almost all attention has focused on the former at the expense of adequate study of the latter.

There has been considerable study of the effects of CO2 on plant growth and physiology. Nobody has shown that in the field plants are more productive in a higher CO2 environment. There was a study claiming that CO2 increases have lead to increased mass of foliage worldwide, but as the authors admit there are MANY confounding factors. This sort of evidence should be considered, but I find it interesting that those advocating doing nothing about AGW leap on such a thin bit of evidence which seems to support them and discount the vast countervailing evidence of great harm and damage to the environment overall, and ignore the high uncertainties in their evidence while leaping at any chance to manufacture doubt about things they don't like.

The consensus is and has been that at best, if we're lucky, added CO2 might provide some limited benefit which at lower warming levels might lead to higher productivity in northern temperate regions. However this added productivity will still be bought at a very significant investment in adaptation as we have to make rapid land use changes, etc. As temperature excursion exceeds 1.5-2C (almost certain as far as we know even if radical action is taken) the net effects rapidly become negative and extremely expensive.

Basically what we're going to see is a LARGE and complex set of changes in the biosphere in response to AGW. To imagine that fortuitously there will be some sort of silver lining in this that just happens to cancel out and make up for the obvious badness seems like wishful thinking to me. Its great if we benefit from higher plant productivity, but this is by no means a foregone conclusion. OTOH things like sea level rise, ocean acidification, disruptions in land use, growth of desert regions, etc are all well-documented and known negative effects of warming/CO2. There may also be unknown effects. Because human society thrives under specific conditions most unknown effects statistically are likely to be negative to some degree.

In other words the ability of some plants to close a few extra stomata and save some water is great, but remember that there are other limits to plant growth, and where water becomes less available, as it does in dry regions with AGW, the long-term net benefit is at best uncertain.

When considering the potential costs of higher levels of CO2, it is also relevant to consider the potential benefits. NASA satellite photography has shown a remarkable greening of the Earth over the past 30 years.

Which is due to what, exactly? There have been plenty of things going on over the last 30 years that can lead to vegetation changes. Logging reforms, acid rain draw-down, "save the rainforest" campaigns, changes in the way people use land, etc. etc. Remember that simple correlations are often not causations.

Quote:

What are the relative costs and benefits of higher CO2? Almost all attention has focused on the former at the expense of adequate study of the latter.

This isn't really true. Studies have been done on the effects of higher CO2 levels (and the warming that generally follows). That includes benefits and draw-backs.

When considering the potential costs of higher levels of CO2, it is also relevant to consider the potential benefits. NASA satellite photography has shown a remarkable greening of the Earth over the past 30 years.

Water requirements for plants - including food crops - especially in arid and semiarid areas are strongly affected by CO2...

What are the relative costs and benefits of higher CO2? Almost all attention has focused on the former at the expense of adequate study of the latter.

“The very real positive externality of inadvertent atmospheric CO2 enrichment must be considered in all studies examining the [social cost of carbon]; and its observationally-deduced effects must be given premier weighting over the speculative negative externalities presumed to occur in computer model projections of global warming,” the study concluded. “Until that time, little if any weight should be placed on current [social cost of carbon] calculations.”

When considering the potential costs of higher levels of CO2, it is also relevant to consider the potential benefits. NASA satellite photography has shown a remarkable greening of the Earth over the past 30 years.

Which is due to what, exactly? There have been plenty of things going on over the last 30 years that can lead to vegetation changes. Logging reforms, acid rain draw-down, "save the rainforest" campaigns, changes in the way people use land, etc. etc. Remember that simple correlations are often not causations.

Quote:

What are the relative costs and benefits of higher CO2? Almost all attention has focused on the former at the expense of adequate study of the latter.

This isn't really true. Studies have been done on the effects of higher CO2 levels (and the warming that generally follows). That includes benefits and draw-backs.

Such as primarily an increase in rainfall in most areas. Remember, this is a known and documented effect of AGW. In fact the methodology of the study he's referring to was to study dry regions.

When considering the potential costs of higher levels of CO2, it is also relevant to consider the potential benefits. NASA satellite photography has shown a remarkable greening of the Earth over the past 30 years.

Water requirements for plants - including food crops - especially in arid and semiarid areas are strongly affected by CO2. Dry climate plants - including many food crops - have a waxy cuticle covering their leaves to reduce water loss. For these plants, most water loss occurs through the stroma, variable size pores in the leaf surface that allow CO2 to enter the photosynthetic apparatus, but which also allow water vapor to leave. Many real ecologists (I don't mean newspaper journalists) have said that the biggest upcoming ecological challenge is likely to be the availability of adequate water of suitable quality for crop irrigation. The largest aquifer in the US Midwest is being unsustainably mined (water pumping exceeding recharge) for irrigation water. This is true for many other places, including much of China and India.

Rain forests will not benefit much from higher CO2 since the limiting factor for plant growth there is solar energy, almost all of which is captured by plants, very little reaching the forest floor. Irrigated corn, wheat, etc., are a different story - available water is the key. Higher CO2 levels mean smaller stroma (smaller directly in proportion to the CO2 concentration) and hence less water needed for irrigation.

What are the relative costs and benefits of higher CO2? Almost all attention has focused on the former at the expense of adequate study of the latter.

There has been considerable study of the effects of CO2 on plant growth and physiology. Nobody has shown that in the field plants are more productive in a higher CO2 environment. There was a study claiming that CO2 increases have lead to increased mass of foliage worldwide, but as the authors admit there are MANY confounding factors. This sort of evidence should be considered, but I find it interesting that those advocating doing nothing about AGW leap on such a thin bit of evidence which seems to support them and discount the vast countervailing evidence of great harm and damage to the environment overall, and ignore the high uncertainties in their evidence while leaping at any chance to manufacture doubt about things they don't like.

The consensus is and has been that at best, if we're lucky, added CO2 might provide some limited benefit which at lower warming levels might lead to higher productivity in northern temperate regions. However this added productivity will still be bought at a very significant investment in adaptation as we have to make rapid land use changes, etc. As temperature excursion exceeds 1.5-2C (almost certain as far as we know even if radical action is taken) the net effects rapidly become negative and extremely expensive.

Basically what we're going to see is a LARGE and complex set of changes in the biosphere in response to AGW. To imagine that fortuitously there will be some sort of silver lining in this that just happens to cancel out and make up for the obvious badness seems like wishful thinking to me. Its great if we benefit from higher plant productivity, but this is by no means a foregone conclusion. OTOH things like sea level rise, ocean acidification, disruptions in land use, growth of desert regions, etc are all well-documented and known negative effects of warming/CO2. There may also be unknown effects. Because human society thrives under specific conditions most unknown effects statistically are likely to be negative to some degree.

In other words the ability of some plants to close a few extra stomata and save some water is great, but remember that there are other limits to plant growth, and where water becomes less available, as it does in dry regions with AGW, the long-term net benefit is at best uncertain.

You have overlooked my primary point: the effect of higher CO2 levels on reducing the water consumption of plants, especially crops, in arid and semi-arid areas. More rain will help increase food production in these areas, reduce irrigation water consumption, and increase aquifer recharge. The expected size of these effects is relatively small compared to that of the reduction in water loss by evapotranspiration from leaves due to smaller stroma sizes.

Increased CO2 levels have long been commercially used in greenhouses, particularly for high value productsm such as marijuana. This is not what I'm referring to. My point regarded the effect of CO2 on plant water requirements, which is an entirely different effect.

You have overlooked my primary point: the effect of higher CO2 levels on reducing the water consumption of plants, especially crops, in arid and semi-arid areas. More rain will help increase food production in these areas, reduce irrigation water consumption, and increase aquifer recharge.

You have overlooked my primary point: the effect of higher CO2 levels on reducing the water consumption of plants, especially crops, in arid and semi-arid areas. More rain will help increase food production in these areas, reduce irrigation water consumption, and increase aquifer recharge.

You have overlooked my primary point: the effect of higher CO2 levels on reducing the water consumption of plants, especially crops, in arid and semi-arid areas. More rain will help increase food production in these areas, reduce irrigation water consumption, and increase aquifer recharge. The expected size of these effects is relatively small compared to that of the reduction in water loss by evapotranspiration from leaves due to smaller stroma sizes.

Increased CO2 levels have long been commercially used in greenhouses, particularly for high value productsm such as marijuana. This is not what I'm referring to. My point regarded the effect of CO2 on plant water requirements, which is an entirely different effect.

Trust me, I know about it. I'm pretty sure I mentioned it, maybe not in the post you're quoting but its in there. This effect, while real, is also of less than clear utility in the real world. For one thing plants need to move specific amounts of material both up and down their stems, which demands specific amounts of transpiration, so there are minimums that any plant can attain and still function. The ONLY evidence that this is an important effect is one survey of satellite data, which can be interpreted in multiple ways. It might be nice, but to think that this one effect somehow mitigates all of climate change and turns CO2 into a huge benefit that offsets $100's of billions a year of damage and large scale dislocation seems like a very weak sort of position to take. If that is the best you guys can do, well, its just not going to be enough. At the very least there needs to be a LARGE amount more study of the effects of CO2 in the real world on plants in all different environments. Even assuming that we're fortunate enough that we CAN maintain agricultural production due to this convenient blessing how does this address the large costs of adapting our agriculture to new conditions or all the OTHER costs of climate change and CO2 release. Aren't we STILL much better off just not creating the problem to start with?

You have overlooked my primary point: the effect of higher CO2 levels on reducing the water consumption of plants, especially crops, in arid and semi-arid areas. More rain will help increase food production in these areas, reduce irrigation water consumption, and increase aquifer recharge.

I was replying to Alhazred; increased rainfall was his claim, not mine.

My statement was about the effects of increased CO2 levels on plant water consumption in arid and semi arid areas.

While it is true that overall rainfall world-wide should increase, evaporation will increase proportionately, and the rain is likely to fall more in areas which already have enough, or too much, and dry areas are likely to become drier, and move/expand into adjacent areas. Its really quite hard to say what the net effect will be. What is fairly certain is that changing conditions will require expensive adaptations, which is kind of the point. Nobody claims we cannot survive climate change within reason, but its quite easy to see that it could be VERY expensive.

The problem here really IMHO is that you pick out specific arguments that there are some possible benefits, but you ignore even considering the 1000's of other ways in which there will be or could be costs. Almost anything we haven't anticipated or fail to deal with effectively will be a negative. There are very few ways that the suitability of the Earth is likely to increase, and vastly many ways statistically that it is likely to become less suitable or convenient for us, all of which will result in costs. Even the people writing papers on social costs like Hitz and Tol all agree that the downsides are so potentially vast and unknown that they are not worth the few specific potential advantages, none of which are certain.